Oil burner electric igniter



D 2, 1958 R. w. QUALLEY 2,862,547

- on. BURNER ELECTRIC IGNITER o a o q a o la n /4 a o n \1 a c i o a o a o c n mmiuu I20 K LINE IN VEN TOR."

ATTORNEYS.

United States Pa n 7 2,862,547 on. BURNER ELECTRIC IGNITER Application October 19, 1953, Serial No. 386,836 3 Claims. (Cl. 158-91) This invention relates to an oil burner electric igniter. The invention is particularly useful in connection with an oil burner of the pot type, but it will be obvious that the invention is applicable to other uses.

An electric igniter for an oil burner has presented a problem 'over the years. When the igniter is heated to ignition temperature and maintained at such temperature, it is found that the prolonged operation results in burning up the resistance coil. On the other hand, when the igniter is turned off after each igniting operation, it is found that carbon formation on the point of the igniter near the fuel renders it ineifective after a period of operation. Further, it is diflicult toignite the fuel from cold condition while employing an igniter element encrusted with carbon. As a result of the foregoing difiiculties, a commercially operable electric igniter has not been produced through the years in spite of the need for such a device.

An object of the present invention is to provide an igniter whichis effective for igniting oil fuel while at the same time substantially preventing carbon formation and remaining in effective condition over long periods of time. A further object is to provide an oil burner electric igniter and a circuit therefor which is eflective in quickly bringing the igniter to an ignition temperature while, after the ignition is brought about, reducing the current flow through the resistance element of the igniter so that it will last an almost indefinite period of time. A still further object is to provide an igniter which is effective not only for igniting the fuel but also for maintaining the fuel in condition for quick ignition when the temperature of the igniter is momentarily raised. Other specific objects and advantages will appear as the specification proceeds.

The invention is shown, in an illustrative embodiment, by the accompanying drawing, in which- Figure 1 is a side view in elevation of a pot burner equipped with an igniter embodying my invention, a portion of the structure being shown in vertical section; Fig. 2, a diagrammatic view of a wiring layout which may be employed; and Fig. 3, a diagrammatic view of a modified form of wiring layout that may be employed.

In the illustration given, 10 designates a pot burner having an oil inlet 11, through which oil to be burned may be fed onto the bottom 12 of the burner. The burner pot may be provided with a batlle plate 13 and the side walls of the burner may be provided with air inlets 14, as shown more clearly in Fig. 1. It will be understood that the burner pot shown is merely illustrative of a great variety of burner pots or oil burners that may be used.

Into the burner pot near the oil inlet 11, extends an igniter 15, which is equipped interiorly with a resistance element so that when the resistance element is subjected to higher voltage, the ignition portion of the igniter may be raised to an ignition temperature for igniting the oil vapors.

In Fig. 2, the resistance element 16 of the igniter is shown diagrammatically. From one end of the igniter subjected to a lower or standby voltage.

2,862,547 Patented Dec. 2, 1958 ice element 16 a lead 17 extends to the coils 18 of a transformer 19. A lead 20 extends from the other end of the coil 18 to a contact point 21. A second lead 22 extends from an intermediate point of the coil 18 :and leads to a contact point 23. The transformer 19 is coupled with the inlet line 24 which passes through the coil 25 of the transformer and back through lead 26.

A switch 27 is biased by spring 28 against contact 23, but may be manually swung to a position in contact with the point 21.

In the operation of the structure shown in Fig. 2, when the operator desires a higher voltage so as to bring the resistance element 16 to an ignition temperature, the switch 27 is swung manually over into engagement with contact 21. The voltage produced by the entire transformer thus passes through lead 20, contact 21, switch 27 and lead 29 to the resistance element 16, the current flowing back through lead 17 to the transformer coil 18, as shown in the wiring layout. After ignition has occurred and the operator releases the switch 27, it is drawn by spring 28 backwardly into engagement with the contact 23 and a reduced voltage is impressed upon the current passing through lead 22, contact 23, switch 27, lead 29, and resistance through lead 17 to the portion of the transformer represented by the coil 18. p

The result of the foregoing is to momentarily bring the voltage in the circuit of the resistance 16 to a higher voltage capable of producing ignition, while, after ignition has occurred, the resistance element 16 is then By way of example, the circuit may be brought to 115 volts in order to bring about the ignition temperature of the coil 16,

and thereafter, when theswitch is brought back into engagement with contact 23, the circuit has a standby voltage of volts. For a specific ignition device, the volts is sufficient to produce ignition, while the 90 volts does not produce an ignition temperature but instead maintains the igniter at a warming temperature. The latter temperature is desirable in that it maintains the oil body adjacent the igniter 15 in a fluid condition and, therefore, in condition for quick ignition when the circuit is subjected to the full voltage of the transformer.

While I have suggested a certain voltage as favorable for ignition and a certain voltage which may be desirable as a standby voltage, it will be understood that such voltages are purely illustrative and :a wide variation in the voltages will occur depending upon the construction of the resistance element, its cross-sectional area, material, and to other conditions. It is suflicient to state that the circuit and the resistance will be so correlated as to produce, when the circuit is subjected to higher voltage, the desired ignition temperature while, at the reduced voltage, the igniter is simply maintained at a warm temperature which is sufiicient to prevent the accumulation of carbon on the igniter and to keep the oil adjacent the igniter in a condition for ready ignition.

In the modification illustrated in Fig. 3, the resistance element is designated by the numeral 30. The incoming current passes through lead 31 and thence through resistance 30 and through .a lead 32 to the contact point 33. When the switch 34 is swung into engagement with the contact 33, the full voltage of the system is impressed upon the resistance 30 to raise it to an igniting temperature. When the switch 34 is drawn upwardly by the spring 35 into engagement with the contact 36, the current then flows through the resistor 37 and then at a reduced voltage through lead 38 to the igniter resistance element 30. In this modification, the employment of a resistance 37 is shown for the purpose of reducing the normally high current of the circuit to a low current 16, the current then flowing back I for the standby period when it is desired that the igniter shallbe maintained at a warm, but below an igniting, temperature.

While,-in the illustrations given, I have setforth two methods of varying the current voltage which is impressed upon the system "at any one time bythe throwing of a switch, it will be understood that many. other electrical methods and devices may-be employed for varying such voltage, and it is sufiicient, for the purpose of'the present invention, if, in the throwing of the switch against one contact, a light or low current or voltage is produced in the circuit leading to the resistance element 16 or 30, while, when the switch swings to engagement with an opposite contact, a heavy or highcurrent or vvoltage is produced in the circuit so as to cause the. resistance element 16 or 30 to becomeeffective in igniting oil vapors.

It will be understood that the switch described in the foregoing specificationmay be either a manually-operated switch or an automatic switch, and mechanism may be provided for bringing the switch into operation at timed intervals.

While, in the foregoing specification, I have set forth certain structures and circuit layouts in considerable detail for the purpose of illustrating certain embodiments of the invention, it will be understood that such details may be varied widely by those skilled in the art without .departing from the spirit of my invention.

1 claim:

1. In an electrically-ignitable oil burner, a burner pot equipped with an inlet adjacent the bottom thereof for directing oil onto said bottom, means for supplying air to the lower portion of the pot, an igniter member supported in said pot and having an end equipped with an electric resistance element adjacent the oil in the bottom of the pot, means maintaining said electric resistance element under a voltage which maintains said end below an ignition temperature but at an elevated temperature 43. for keeping said oil in a condition for ready ignition and said end substantially free of carbon encrustation, and switch-controlled means for increasing the voltage upon said element to bring it normally to ignition temperature.

2. The structure of claim 1, in which a voltage of about 115 volts produces ignition and a voltage of about 90 volts maintains said electric resistance element below an ignition temperature but at an elevated temperature for keeping said oil in a condition for ready ignition and said end substantially free of carbon encrustation.

3. An electrically-ignita-ble oil burner, comprising a burner pot, means for supplying air to the lower portion of the pot, an oil fuel inlet adjacent the bottom of said pot for supplying oil onto the pot bottom, an igniter member supported in said pot and equipped with an ignition end having therein an electric resistance element, said end being adjacent the oil in the bottom of the pot, means impressing upon said element a current fiow'under a voltage which maintains the temperature of said end sufiiciently high to keep said oil in a condition for ready ignition but below an ignition temperature and which maintains said end substantially free of carbon encrustation,

- and a spring-actuated switch-controlled means for raising the voltage .of the current flow to said element to bring said element to .an ignition temperature upon the actuation of said switch.

References Cited in the file ofthis patent UNITED STATES PATENTS Switzerland Apr. 2, 1951 

